List of Illinois Milkweeds
Illinois Milkweed Species to Include in your Butterfly Garden
There are eighteen native species of Illinois milkweeds (Asclepias spp.) and one adventive species that can be grown for Monarch Butterflies and other insects. Milkweeds are an important host species for Monarch, Queen, and Soldier Butterflies. The Monarch butterfly in particular uses the cardenolides found in the milky sap of milkweeds to give an unpleasant taste to predators. These plants are also an important nectar source to all insects visiting your pollinator garden.
1. Clasping Milkweed (Asclepias amplexicaulis), an Illinois Milkweed for Dry Soils
Clasping Milkweed (Asclepias amplexicaulis): This Illinois milkweed species is native throughout the state with a scattered distribution in the south (Kartesz 2015). In the wild, clasping milkweed grows in dry woodlands, prairies, meadows, and roadsides having sandy or gravelly soil. Growing up to 3 feet tall, this plant has greenish-pink, red, brown, to purple flowers bloom from March to September.
In a garden setting, clasping milkweed is hardy in zones 3-9, requires full sun to part-shade with dry sandy soil. Seeds for clasping milkweed seeds can be purchased in the McMullen House Bed & Breakfast Garden Shop.
2. Poke Milkweed (Asclepias exaltata), an Illinois Milkweed for Moist Soils
Poke Milkweed (Ascelpias exaltata): This Illinois milkweed species is native throughout the state (Kartesz 2015). In the wild, this milkweed is found in moist woods, roadsides, and the edges of woods. Growing 2 to 6 feet tall, it is one of the taller milkweeds, and has flowers that are white to green with accents of rose, purple, or blue. The flowers bloom from April to August.
In a garden setting, poke milkweed is hardy in zones 3-9, requires part-shade to shade, and moist soil. Poke milkweed seeds can be purchased in the McMullen House Bed & Breakfast Garden Shop.
3. Swamp Milkweed (Asclepias incarnata), an Illinois Milkweed for Moist Soils
Swamp Milkweed (Asclepias incarnata): This Illinois milkweed has two subspecies, ssp. incarnata and ssp. pulchra. The former is found throughout the state (hardy in zones 3-9), while the latter is not found in Illinois (Kartesz 2015). Like the name suggests this plant is found in wet places such as the shores of streams, lakes, ponds, and other wetlands. This is one of the taller milkweeds growing from 3 to 5 feet tall. The flowers, which bloom from July to September, are generally a pink to red color, but there is also a white cultivar (pictured below).
In a garden setting, swamp milkweed it is hardy in zones 3-9, requires full sun to part-shade and prefers moist to medium moisture soil, but can exist in drier soil in a landscape setting. Seeds for swamp milkweed can be purchased in the McMullen House Bed & Breakfast Garden Shop.
4. Side-Cluster Milkweed (Asclepias lanuginosa), a Rare Illinois Milkweed
Side-cluster Milkweed (Asclepias lanuginosa): This Illinois milkweed is native and rare in the northern part of the state (Kartesz 2015). In the wild, side-cluster milkweed grows in prairies and sandhills having full sun. The height of this milkweed is variable and ranges from 0.5 to 4 feet tall, but can grow up 6 feet in favorable places. The flowers range in color from green to cream and bloom from May to July.
In a garden setting, while side-cluster milkweed is hardy in zones 4-7, it is rare and not in the horticultural trade.
5. Long-leaf Milkweed (Asclepias longifolia), an Illinois Milkweed for Moist Soils
Long-leaf Milkweed (Asclepias longifolia): This Illinois milkweed has two varieties, var. hirtella and var. longifolia. Of these var. hirtella occurs throughout the state (Kartesz 2015). In the wild, long-leaf milkweed grows in moist areas and wetlands such as bogs, swamps, flatwoods, and prairies having full sun. Growing from 1 to 2.5 feet tall, the greenish-white flowers bloom from April to July.
In a garden setting, long-leaf milkweed is hardy in zones 4-9, requires full sun and moist to wet soils.
6. Mead’s Milkweed (Asclepias meadii), a Rare Illinois Milkweed
Mead’s Milkweed (Asclepias meadii): This Illinois milkweed is native and rare generally in the northern part of the state and one county in south (Kartesz 2015). In the wild, Mead’s milkweed grows in tallgrass prairies, hay meadows, and barrens that have full sun. Growing from 1 to 3 feet tall, the greenish-white to yellow flowers bloom from June to July. This plant is federally endangered and is not in cultivation.
7. Oval-leaf Milkweed (Asclepias ovalifolia), an Illinois Milkweed for Well-drained High pH Soil
Oval-leaf Milkweed (Asclepias ovalifolia): This Illinois milkweed is native and rare in the northeastern part of the state (Kartesz 2015). In the wild, oval-leaf milkweed grows in open areas having full sun or partial shade such as prairies, grasslands, savannas, railroad edges, and alluvial terraces. It is one of the shorter milkweeds in Illinois and grows to about 2 feet tall. and has white, pink, or green flowers that bloom from May to August.
In a garden setting, oval-leaf milkweed is hardy in zones 5-9, requires full sun to part-shade and well-drained high pH soil. Oval-leaf milkweed seeds can be purchased in the McMullen House Bed & Breakfast Garden Shop.
8. Aquatic Milkweed (Asclepias perennis), an Illinois Milkweed for Moist Soils
Aquatic Milkweed (Asclepias perennis): This Illinois milkweed is native in the southeastern part of the state (Kartesz 2015). In the wild, aquatic milkweed grows in open areas having full sun or partial shade such as prairies, grasslands, savannas, railroad edges, and alluvial terraces. Growing from 1 to 3.5 feet tall, this milkweed has white, pink, or green flowers that bloom from May to August.
In a garden setting, aquatic milkweed is hardy in zones 5-9, requires full sun to part-sun, and moist soils.
9. Purple Milkweed (Asclepias purpurascens), an Illinois Milkweed for Moist Soils
Purple Milkweed (Asclepias purpurascens): This Illinois milkweed is native throughout the state (Kartesz 2015). In the wild, purple milkweed grows in moist to dry places having full sun to part shade such as swamps, woodlands, meadows, roadsides, and dry fields. Growing up to 6 feet tall, the purple to pink flowers bloom from May to July.
In a garden setting, purple milkweed is hardy in zones 3-8 and requires part-shade, but can handle full sun. Soils should be moist and well-drained, but dry soil can be tolerated. Seeds for purple milkweed can be purchased in the McMullen House Bed & Breakfast Garden Shop.
10. Four-leaf Milkweed (Asclepias quadrifolia), an Illinois Milkweed for Dry Rocky Soils
Four-leaf Milkweed (Asclepias quadrifolia): This Illinois milkweed is native primarily in the western part of the state, with a scattered distribution in the south central area (Kartesz 2015). In the wild, four-leaf milkweed grows in open places with full sun such as roadsides, pastures, and prairies. Growing from 1 to 3 feet, four-leaf milkweed has cream to pink flowers bloom from April to July.
In a garden setting, four-leaf milkweed is hardy in zones 5-8 and grows best in places of full sun to part-shade with dry rocky soils.
11. Slim-leaf Milkweed (Asclepias stenophylla), an Illinois Milkweed for Dry Soils
Slim-leaf Milkweed (Asclepias stenophylla): This Illinois milkweed is native and rare to two counties in the western part of the state (Kartesz 2015). In the wild, slim-leaf milkweed grows in open areas with full sun such as prairies and sandy areas. Growing from 0.5 to 3 feet tall, this milkweed has greenish-white flowers that bloom from June to August.
In a garden setting, slim-leaf milkweed is hardy in zones 3-9, requires full sun and dry sandy or gravelly soils. Seeds of this plant can be purchased in the McMullen House Bed & Breakfast Garden Shop.
12. Sullivant’s Milkweed (Asclepias sullivantii), an Illinois Milkweed for Medium to Dry Soils
Sullivant’s Milkweed (Asclepias sullivantii): This Illinois milkweed is native throughout the state (Kartesz 2015). In the wild, Sullivant’s milkweed grows in open areas with full sun such as prairies, meadows, roadsides, and railroads. Growing from 2 to 5 feet tall, it has pink to purplish flowers that bloom from June to July.
In a garden setting, Sullivant’s milkweed is hardy in zones 3-7, requires full sun, and medium to dry sandy soil. Seeds of this plant can be purchased in the McMullen House Bed & Breakfast Garden Shop.
13. Common Milkweed (Asclepias syriaca), an Illinois Milkweed for all Conditions
Common Milkweed (Asclepias syriaca): This Illinois milkweed is native throughout the state (Kartesz 2015). In the wild, common milkweed is found in open areas such as fields, pastures, and roadsides, where it can receive full sun. One of the taller milkweeds, it can grow up to 6 feet tall and has flowers ranging from pink, greenish-purple, greenish-white, to white and bloom from June to August.
In a garden setting, common milkweed is hardy in zones 3-9 and grows in almost any exposure and soil condition, though it prefers full sun. Seeds of this plant can be purchased in the McMullen House Bed & Breakfast Garden Shop.
14. Butterfly Weed (Asclepias tuberosa), an Illinois Milkweed for all Conditions
Butterfly Weed (Asclepias tuberosa): This Illinois milkweed is one of the most common for butterfly gardeners on the east coast of the United States. In Illinois, subspecies interior of this species is native throughout the state. Subspecies tuberosa, is native in one county in the south (Kartesz 2015). In the wild, butterfly weed grows in open areas with full sun such as fields, roadsides, and open woods. Growing from 1 to 3 feet tall, the characteristically orange flowers bloom throughout the summer and sometimes into the autumn.
In a garden setting, butterfly weed is hardy from zones 3-9 and grows in most conditions, but prefers full sun if possible. Seeds of butterfly weed can be purchased in the McMullen House Bed & Breakfast Garden Shop.
15. Red-Ring Milkweed (Asclepias variegata), an Illinois Milkweed for Dry Rocky or Sandy Soils
Red-Ring Milkweed (Asclepias variegata): This Illinois milkweed is native in the southern part of the state (Kartesz 2015). In the wild, red-ring milkweed grows thickets, open woods, and roadsides that are dry and rocky or sandy. Growing from 1 to 3 feet tall, this milkweed has white flowers have a purple or red ring that bloom from May to July.
In a garden setting, red-ring milkweed is hardy in zones 3-9, require part-sun to part-shade and dry rocky or sandy soils. Seeds of red-ring milkweed can be purchased in the McMullen House Bed & Breakfast Garden Shop.
16. Whorled Milkweed (Asclepias verticillata), an Illinois Milkweed for Medium to Dry Soils
Whorled Milkweed (Asclepias verticillata): This Illinois milkweed is native throughout the state (Kartesz 2015). In the wild, whorled milkweed grows in open areas such as meadows and fields, where it can take advantage of full sun. Growing up to 3 feet tall, this milkweed has green to white flowers that bloom from May to September.
In a garden setting, whorled milkweed is hardy in zones 3-9, requires full sun to part-shade, and medium to dry soil. Seeds for this plant can be purchased at the McMullen House Bed & Breakfast Garden Shop.
17. Green Comet Milkweed (Asclepias viridiflora), an Illinois Milkweed for Medium to Dry Soils
Green Comet Milkweed (Asclepias viridiflora): This Illinois milkweed is native throughout the state (Kartesz 2015). In the wild, green comet milkweed grows in open areas such as meadows and fields where there is full sun. Growing up to 3 feet, it has flowers that begin as a green color but age to become yellow and purple tinged.
In a garden setting, green comet milkweed is hardy in zones 3-9, requires full sun to part-shade, and medium to dry sandy soil. Seeds for green comet milkweed can be purchased at the McMullen House Bed & Breakfast Garden Shop.
18. Green Milkweed (Asclepias viridis), an Illinois Milkweed for Medium to Dry High pH Soils
Green Milkweed (Asclepias viridis): This Illinois milkweed is native to the southern part of the state (Kartesz 2015). In the wild, green milkweed grows in open areas where it can receive full sun and have high pH such as glades, prairies, roadsides, and pastures. Growing from 0.5 to 2 feet tall it is one of the shortest milkweeds in Illinois. This milkweed has green, yellowish-green, or white flowers bloom from April to October.
In a garden setting, this plant is hardy in zones 5-9, requires full sun, and medium to dry soils with a high pH. Seeds for green milkweed can be purchased at the McMullen House Bed & Breakfast Garden Shop.
When selecting your Illinois milkweed, be sure to make sure that it grows in your zone and habitat.
An Additional Illinois Milkweed to Consider
1. Showy Milkweed (Asclepias speciosa), an Adventive Illinois Milkweed for Medium to Dry Soils
Showy Milkweed (Asclepias speciosa): This Illinois milkweed is adventive in the state, meaning is has been naturalized, but is not technically native (Kartesz 2015). It is native however to the state of Iowa to the west. In the wild, showy milkweed grows in open areas such as roadsides, fields, and woodlands that are mesic to dry. Growing from 1 to 3 feet tall, showy milkweed has flowers that are purple to pink in color and bloom from April to June.
In a garden setting, this plant is hardy in zones 3-9, requires full sun, and medium to dry soil. Seeds for showy milkweed can be purchased in the McMullen House Bed & Breakfast Garden Shop.
References for Illinois Milkweeds
- Kartesz, J.T. The Biota of North America Program (BONAP). 2015. Taxonomic Data Center. Link to website. Chapel Hill, N.C. [maps generated from Kartesz, J.T. 2015. Floristic Synthesis of North America, Version 1.0. Biota of North America Program (BONAP). (in press)]
